Tampa Bay home prices put in one of the worst performances on the S&P/Case-Shiller home price index, falling 7.4 percent between January 2009 and January 2010.

Tampa's annual housing devaluation was the second steepest on the 20-city index that tracks repeat sales of individual homes. Las Vegas' 17.4 percent plunge led the nation. Tampa Bay tied with Detroit for second worst.

Tampa Bay home prices had leveled since spring 2009, but modest depreciation resumed late in the year. Foreclosure homes — up to half of all sales — acted as a drag.

"The rebound in housing prices seen last fall is fading," S&P economist David Blitzer said.

As housing equity disappeared, more homeowners sunk into foreclosure, unable to refinance their ways out of money troubles aggravated by high unemployment.

"The Sun Belt states — Southern California, Arizona, Nevada and Florida — went through the roof and are now down in the cellar," he said.

Since Tampa Bay home prices peaked in July 2006, as recorded by Case-Shiller, they have fallen 42 percent. Prices almost duplicate what they were in May 2003.

While few homeowners cheer price chops, rising home sales have helped blunt the sharp edge. Buyers flush with home buyer tax credits of $8,000 or $6,500 have pecked away at the region's housing glut.

Downtown St. Petersburg's Signature Place condo tower sold 50 units at auction this month, prices from which became the new baseline. Another 32 condos sold post-auction at discounts up to 40 percent, developers said.

"Sellers are starting to get real with price," said St. Petersburg Realtor Frank Malowany, who specializes in expensive homes on the water. "And banks are willing to haggle more on the homes they own."

Some economists predict further price weakening with the elimination of the home buyer tax credit after April 30. Interest rates on home loans should creep up as the Federal Reserve unwinds its involvement in the mortgage market.

And despite a string of government incentives designed to shield homeowners from foreclosure, the mortgage redefault rate hovers above 50 percent, the federal government reported last week.

"It is only a matter of time before the index records a double-dip in prices," wrote Paul Dales of Capital Economics, which forecasts a 5 percent drop.

The Golden State emitted a glimmer of good news. The three California markets on the Case-Shiller index — San Diego, Los Angeles and San Francisco — all reported price gains year over year. California's experience often foreshadows the nation's.